314 lines
10 KiB
C++
314 lines
10 KiB
C++
/////////////////////////////////////////////////////////////////////////////
|
|
// Name: my_dll.cpp
|
|
// Purpose: Sample showing how to use wx from a DLL
|
|
// Author: Vaclav Slavik
|
|
// Created: 2009-12-03
|
|
// Copyright: (c) 2009 Vaclav Slavik
|
|
// Licence: wxWindows licence
|
|
/////////////////////////////////////////////////////////////////////////////
|
|
|
|
// ============================================================================
|
|
// declarations
|
|
// ============================================================================
|
|
|
|
// ----------------------------------------------------------------------------
|
|
// headers
|
|
// ----------------------------------------------------------------------------
|
|
|
|
#include "wx/wxprec.h"
|
|
|
|
#ifdef __BORLANDC__
|
|
#pragma hdrstop
|
|
#endif
|
|
|
|
#ifndef __WINDOWS__
|
|
#error "This sample is Windows-only"
|
|
#endif
|
|
|
|
#include "wx/app.h"
|
|
#include "wx/dynlib.h"
|
|
#include "wx/frame.h"
|
|
#include "wx/panel.h"
|
|
#include "wx/sizer.h"
|
|
#include "wx/stattext.h"
|
|
#include "wx/button.h"
|
|
#include "wx/thread.h"
|
|
#include "wx/msgdlg.h"
|
|
#include "wx/msw/wrapwin.h"
|
|
|
|
#include <process.h> // for _beginthreadex()
|
|
|
|
#include "my_dll.h"
|
|
|
|
// ----------------------------------------------------------------------------
|
|
// GUI classes
|
|
// ----------------------------------------------------------------------------
|
|
|
|
class MyDllFrame : public wxFrame
|
|
{
|
|
public:
|
|
MyDllFrame(wxWindow *parent, const wxString& label);
|
|
|
|
void OnAbout(wxCommandEvent& event);
|
|
|
|
wxDECLARE_EVENT_TABLE();
|
|
};
|
|
|
|
|
|
static const int CMD_SHOW_WINDOW = wxNewId();
|
|
static const int CMD_TERMINATE = wxNewId();
|
|
|
|
class MyDllApp : public wxApp
|
|
{
|
|
public:
|
|
MyDllApp();
|
|
|
|
private:
|
|
void OnShowWindow(wxThreadEvent& event);
|
|
void OnTerminate(wxThreadEvent& event);
|
|
};
|
|
|
|
|
|
// ============================================================================
|
|
// implementation
|
|
// ============================================================================
|
|
|
|
// ----------------------------------------------------------------------------
|
|
// MyDllFrame
|
|
// ----------------------------------------------------------------------------
|
|
|
|
wxBEGIN_EVENT_TABLE(MyDllFrame, wxFrame)
|
|
EVT_BUTTON(wxID_ABOUT, MyDllFrame::OnAbout)
|
|
wxEND_EVENT_TABLE()
|
|
|
|
MyDllFrame::MyDllFrame(wxWindow *parent, const wxString& label)
|
|
: wxFrame(parent, wxID_ANY, label)
|
|
{
|
|
wxPanel *p = new wxPanel(this, wxID_ANY);
|
|
wxSizer *sizer = new wxBoxSizer(wxVERTICAL);
|
|
|
|
sizer->Add
|
|
(
|
|
new wxStaticText
|
|
(
|
|
p, wxID_ANY,
|
|
wxString::Format
|
|
(
|
|
"Running using %s\n"
|
|
"wxApp instance is %p, thread ID %ld",
|
|
wxVERSION_STRING,
|
|
wxApp::GetInstance(),
|
|
wxThread::GetCurrentId()
|
|
)
|
|
),
|
|
wxSizerFlags(1).Expand().Border(wxALL, 10)
|
|
);
|
|
|
|
sizer->Add
|
|
(
|
|
new wxButton(p, wxID_ABOUT, "Show info"),
|
|
wxSizerFlags(0).Right().Border(wxALL, 10)
|
|
);
|
|
|
|
p->SetSizerAndFit(sizer);
|
|
|
|
wxSizer *fsizer = new wxBoxSizer(wxVERTICAL);
|
|
fsizer->Add(p, wxSizerFlags(1).Expand());
|
|
SetSizerAndFit(fsizer);
|
|
}
|
|
|
|
void MyDllFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
|
|
{
|
|
wxMessageBox("This window is running in its own thread,\n"
|
|
"using private wxWidgets instance compiled into the DLL.",
|
|
"About",
|
|
wxOK | wxICON_INFORMATION);
|
|
}
|
|
|
|
|
|
// ----------------------------------------------------------------------------
|
|
// MyDllApp
|
|
// ----------------------------------------------------------------------------
|
|
|
|
MyDllApp::MyDllApp()
|
|
{
|
|
// Keep the wx "main" thread running even without windows. This greatly
|
|
// simplifies threads handling, because we don't have to correctly
|
|
// implement wx-thread restarting.
|
|
//
|
|
// Note that this only works if you don't explicitly call ExitMainLoop(),
|
|
// except in reaction to wx_dll_cleanup()'s message. wx_dll_cleanup()
|
|
// relies on the availability of wxApp instance and if the event loop
|
|
// terminated, wxEntry() would return and wxApp instance would be
|
|
// destroyed.
|
|
//
|
|
// Also note that this is efficient, because if there are no windows, the
|
|
// thread will sleep waiting for a new event. We could safe some memory
|
|
// by shutting the thread down when it's no longer needed, though.
|
|
SetExitOnFrameDelete(false);
|
|
|
|
Connect(CMD_SHOW_WINDOW,
|
|
wxEVT_THREAD,
|
|
wxThreadEventHandler(MyDllApp::OnShowWindow));
|
|
Connect(CMD_TERMINATE,
|
|
wxEVT_THREAD,
|
|
wxThreadEventHandler(MyDllApp::OnTerminate));
|
|
}
|
|
|
|
void MyDllApp::OnShowWindow(wxThreadEvent& event)
|
|
{
|
|
wxFrame *f = new MyDllFrame(NULL, event.GetString());
|
|
f->Show(true);
|
|
}
|
|
|
|
void MyDllApp::OnTerminate(wxThreadEvent& WXUNUSED(event))
|
|
{
|
|
ExitMainLoop();
|
|
}
|
|
|
|
|
|
// ----------------------------------------------------------------------------
|
|
// application startup
|
|
// ----------------------------------------------------------------------------
|
|
|
|
// we can't have WinMain() in a DLL and want to start the app ourselves
|
|
IMPLEMENT_APP_NO_MAIN(MyDllApp)
|
|
|
|
namespace
|
|
{
|
|
|
|
// Critical section that guards everything related to wxWidgets "main" thread
|
|
// startup or shutdown.
|
|
wxCriticalSection gs_wxStartupCS;
|
|
// Handle of wx "main" thread if running, NULL otherwise
|
|
HANDLE gs_wxMainThread = NULL;
|
|
|
|
|
|
// wx application startup code -- runs from its own thread
|
|
unsigned wxSTDCALL MyAppLauncher(void* event)
|
|
{
|
|
// Note: The thread that called run_wx_gui_from_dll() holds gs_wxStartupCS
|
|
// at this point and won't release it until we signal it.
|
|
|
|
// We need to pass correct HINSTANCE to wxEntry() and the right value is
|
|
// HINSTANCE of this DLL, not of the main .exe, use this MSW-specific wx
|
|
// function to get it. Notice that under Windows XP and later the name is
|
|
// not needed/used as we retrieve the DLL handle from an address inside it
|
|
// but you do need to use the correct name for this code to work with older
|
|
// systems as well.
|
|
const HINSTANCE
|
|
hInstance = wxDynamicLibrary::MSWGetModuleHandle("my_dll",
|
|
&gs_wxMainThread);
|
|
if ( !hInstance )
|
|
return 0; // failed to get DLL's handle
|
|
|
|
// IMPLEMENT_WXWIN_MAIN does this as the first thing
|
|
wxDISABLE_DEBUG_SUPPORT();
|
|
|
|
// We do this before wxEntry() explicitly, even though wxEntry() would
|
|
// do it too, so that we know when wx is initialized and can signal
|
|
// run_wx_gui_from_dll() about it *before* starting the event loop.
|
|
wxInitializer wxinit;
|
|
if ( !wxinit.IsOk() )
|
|
return 0; // failed to init wx
|
|
|
|
// Signal run_wx_gui_from_dll() that it can continue
|
|
HANDLE hEvent = *(static_cast<HANDLE*>(event));
|
|
if ( !SetEvent(hEvent) )
|
|
return 0; // failed setting up the mutex
|
|
|
|
// Run the app:
|
|
wxEntry(hInstance);
|
|
|
|
return 1;
|
|
}
|
|
|
|
} // anonymous namespace
|
|
|
|
// ----------------------------------------------------------------------------
|
|
// public DLL interface
|
|
// ----------------------------------------------------------------------------
|
|
|
|
extern "C"
|
|
{
|
|
|
|
void run_wx_gui_from_dll(const char *title)
|
|
{
|
|
// In order to prevent conflicts with hosting app's event loop, we
|
|
// launch wx app from the DLL in its own thread.
|
|
//
|
|
// We can't even use wxInitializer: it initializes wxModules and one of
|
|
// the modules it handles is wxThread's private module that remembers
|
|
// ID of the main thread. But we need to fool wxWidgets into thinking that
|
|
// the thread we are about to create now is the main thread, not the one
|
|
// from which this function is called.
|
|
//
|
|
// Note that we cannot use wxThread here, because the wx library wasn't
|
|
// initialized yet. wxCriticalSection is safe to use, though.
|
|
|
|
wxCriticalSectionLocker lock(gs_wxStartupCS);
|
|
|
|
if ( !gs_wxMainThread )
|
|
{
|
|
HANDLE hEvent = CreateEvent
|
|
(
|
|
NULL, // default security attributes
|
|
FALSE, // auto-reset
|
|
FALSE, // initially non-signaled
|
|
NULL // anonymous
|
|
);
|
|
if ( !hEvent )
|
|
return; // error
|
|
|
|
// NB: If your compiler doesn't have _beginthreadex(), use CreateThread()
|
|
gs_wxMainThread = (HANDLE)_beginthreadex
|
|
(
|
|
NULL, // default security
|
|
0, // default stack size
|
|
&MyAppLauncher,
|
|
&hEvent, // arguments
|
|
0, // create running
|
|
NULL
|
|
);
|
|
|
|
if ( !gs_wxMainThread )
|
|
{
|
|
CloseHandle(hEvent);
|
|
return; // error
|
|
}
|
|
|
|
// Wait until MyAppLauncher signals us that wx was initialized. This
|
|
// is because we use wxMessageQueue<> and wxString later and so must
|
|
// be sure that they are in working state.
|
|
WaitForSingleObject(hEvent, INFINITE);
|
|
CloseHandle(hEvent);
|
|
}
|
|
|
|
// Send a message to wx thread to show a new frame:
|
|
wxThreadEvent *event =
|
|
new wxThreadEvent(wxEVT_THREAD, CMD_SHOW_WINDOW);
|
|
event->SetString(title);
|
|
wxQueueEvent(wxApp::GetInstance(), event);
|
|
}
|
|
|
|
void wx_dll_cleanup()
|
|
{
|
|
wxCriticalSectionLocker lock(gs_wxStartupCS);
|
|
|
|
if ( !gs_wxMainThread )
|
|
return;
|
|
|
|
// If wx main thread is running, we need to stop it. To accomplish this,
|
|
// send a message telling it to terminate the app.
|
|
wxThreadEvent *event =
|
|
new wxThreadEvent(wxEVT_THREAD, CMD_TERMINATE);
|
|
wxQueueEvent(wxApp::GetInstance(), event);
|
|
|
|
// We must then wait for the thread to actually terminate.
|
|
WaitForSingleObject(gs_wxMainThread, INFINITE);
|
|
CloseHandle(gs_wxMainThread);
|
|
gs_wxMainThread = NULL;
|
|
}
|
|
|
|
} // extern "C"
|